38 resultados para adhesive


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A pneumatic vehicle is provided with a first and second sub-assembly. The first sub-assembly has a chassis supporting an air tank. The second sub-assembly has part of the vehicle body and is bonded to the first-sub-assembly using a structural adhesive. Another pneumatic vehicle is provided with a first and second sub-assembly. The first sub-assembly has a chassis, air tank, part of the vehicle body, a pair of B-pillars, and a pair of rear rails. The second sub-assembly has a part of the vehicle body, a pair of A-pillars, and a pair of roof rails. A vehicle seat is provided with a seat base and upright seat back providing a seating area. A bladder located in the central region of the seating area inflates to provide two bucket seats, and deflates to provide a bench seat. The vehicle seat also has inflatable inserts to provide cushioning.

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We present an approach for the efficient design of polarization insensitive polymeric optical waveguide devices considering stress-induced effects. In this approach, the stresses induced in the waveguide during the fabrication process are estimated first using a more realistic model in the finite element analysis. Then we determine the perturbations in the material refractive indices caused by the stress-optic effect. It is observed that the stresses cause non-uniform optical anisotropy in the waveguide materials, which is then incorporated in the modal analysis considering a multilayer structure of waveguide. The approach is exploited in the design of a Bragg grating on strip waveguide. Excellent agreement between calculated and published experimental results confirms the feasibility of our approach in the accurate design of polarization insensitive polymer waveguide devices.

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A pneumatic vehicle is provided with a first sub-assembly with a chassis, part of the vehicle body, a pair of B-pillars, a pair of rear rails, wheels, an elongate aluminum compressed load bearing air tank oriented longitudinally in the chassis, side panels connected to the tank and the wheels, a heat exchanger to heat the compressed air, and an air motor driven by the heated, compressed air and connected to a wheel. A ventilation system has a restrictive solenoid valve for directing air to the heat exchanger. The air tank is provided with a carbon filament reinforced plastic layer, and a fiberglass and aramid-fiber layer. A second sub-assembly includes part of the vehicle body bonded to the first-sub-assembly using a structural adhesive, a pair of A-pillars, and a pair of roof rails. Seating includes inflatable components for adjustment.

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Fe3Al–Al2O3 double-layer coatings (DC), Fe3Al-Fe3Al/50%Al2O3–Al2O3 triple-layer coatings (TC) and Fe3Al-Al2O3 graded coatings (GC) were produced from a series of Fe3Al/Al2O3 composite powders with different compositions on low carbon steel substrate using PLAXAIR plasma spraying equipment. Friction behaviors and wear resistance of the three kinds of coatings have been investigated under different loads. Tests were carried out using an MRH-3 standard machine, in lineal contact sliding under dry condition against hardmetal, at a sliding velocity of about 1.57 ms−1. Wear rates under different loads were measured and the friction coefficients were recorded. SEM analysis was carried out to identify the wear mechanisms. The results show that the GC has higher wear-resistance than DC and TC. The tribological characteristics of graded coating were different along the depth of the coatings, and the surface of coatings with pure Al2O3 does not show the best wear resistance. The wear rate and friction coefficients were also different under different loads. The failure types of plasma-sprayed Fe3Al-Al2O3 graded coatings in lineal contact were: loosening of ceramic particles, crack nucleation and propagation, brittle fracture, plastic deformation, and adhesive wear.

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There is an increasing demand for high performance composites with enhanced mechanical and electrical properties. Carbon nanofibres offer a promising solution but their effectiveness has been limited by difficulty in achieving directional alignment. Here we report the use of an alternating current (AC) electric field to align carbon nanofibres in an epoxy. During the cure process of an epoxy resin, carbon nanofibres (CNFs) are observed to rotate and align with the applied electric field, forming a chain-like structure. The fracture energies of the resultant epoxy nanocomposites containing different concentrations of CNFs (up to 1.6wt%) are measured using double cantilever beam specimens. The results show that the addition of 1.6wt% of aligned CNFs increases the electrical conductivity of such nanocomposites by about seven orders of magnitudes to 10<sup>-2</sup>S/m and increases the fracture energy, G<inf>Ic</inf>, by about 1600% from 134 to 2345J/m<sup>2</sup>. A modelling technique is presented to quantify this major increase in the fracture energy with aligned CNFs. The results of this research open up new opportunities to create multi-scale composites with greatly enhanced multifunctional properties.

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The fabrication of superhydrophobic surfaces with mechanical durability is challenging because the surface microstructure is easily damaged. Herein, we report superhydrophobic conductive graphite nanoplatelet (GNP)/vapor-grown carbon fiber (VGCF)/polypropylene (PP) composite coatings with mechanical durability by a hot-pressing method. The as-prepared GNP/VGCF/PP composite coatings showed water contact angle (WCA) above 150° and sliding angle (SA) less than 5°. The superhydrophobicity was improved with the increase of VGCF content in the hybrid GNP and VGCF fillers. The more VGCFs added in the GNP/VGCF/PP composite coating, the higher porosity on the surface was formed. Compared to the GNP/PP and VGCF/PP composite coatings, the GNP and VGCF hybrid fillers exhibited more remarkable synergistic effect on the electrical conductivity of the GNP/VGCF/PP composite coatings. The GNP/VGCF/PP composite coating with GNP:VGCF = 2:1 possessed a sheet resistance of 1 Ω/sq. After abrasion test, the rough microstructure of the GNP/VGCF/PP (2:1) composite coating was mostly restored and the composite coating retained superhydrophobicity, but not for the VGCF/PP composite coating. When the superhydrophobic surface is mechanically damaged with a loss of superhydrophobicity, it can be easily repaired by a simple way with adhesive tapes. Moreover, the oil-fouled composite surface can regenerate superhydrophobicity by wetting the surface with alcohol and subsequently burning off alcohol.

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We investigated the anti-cancer activity of alginate coated chitosan nanoparticles (CHNP) encapsulating cell-permeable dominant negative survivin (SR9) with locked nucleic acid (LNA) aptamers targeting EpCAM and nucleolin (termed as "nanobullets") in vitro (2D and 3D cell culture models) and in vivo (colon cancer mouse xenograft model). We incorporated three LNA modifications in each sequence in order to enhance the stability of these aptamers. Confocal microscopy revealed binding of the LNA-aptamers to their specific markers with high affinity. The muco-adhesive nanobullets showed 6-fold higher internalization in cancer cells when compared to non-cancerous cells, suggesting a tumour specific uptake. A higher intensity of nanobullets was observed in both the periphery and the core of the multicellular tumour spheroids compared to non-targeted CHNP-SR9. The nanobullets were found to be the highly effective as they led to a 2.26 fold (p < 0.05) reduction at 24 h and a 4.95 fold reduction (p ≤ 0.001) in the spheroid size at 72 h. The tumour regression was 4 fold higher in mice fed on a nanobullet diet when compared to a control diet. The nanobullets were able to show a significantly high apoptotic (p ≤ 0.0005) and necrotic index in the tumour cell population (p ≤ 0.005) when compared to void NPs. Therefore, our nanoparticles have shown highly promising results and therefore deliver a new conduit towards the approach of cancer-targeted nanodelivery. This journal is

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The fabrication of artificial scaffolds that effectively mimic the host environment of the cell have exciting potential for the treatment of many diseases in regenerative medicine. In particular, appropriately designed scaffolds have the capacity to support, replace, and mediate the transplantation of therapeutic cells in order to regenerate damaged or diseased tissues. To achieve these goals for regeneration, the engineering of an environment structurally similar to the native extracellular matrix (ECM) is necessary in order to closely match the chemical and physical conditions found within the extracellular niche. Recently, self-assembled peptide (SAP) hydrogels have shown great potential for such biological applications due to their inherent biocompatibility, propensity to form higher order structures, rich chemical functionality and ease of synthesis. Importantly, it is possible to control the organization and properties of the target materials as the chemical structure is determined by amino acid sequence. Here, the development of SAP hydrogels as functional cell scaffolds and useful tools in tissue engineering is reviewed.